The skimmers record credit card information when customers swipe their cards, Lafayette police Lt. Scott Galloway said. That information is then used to duplicate those cards and tap into customers' credit or debit accounts.

"You would never know there's a skimming device in there," he said, explaining there were no overt signs of the tampering because the skimmers were installed inside the pumps.

The skimmers were discovered after the pumps broke and a technician opened up the access panel to the pump's electronics, Galloway said.

Connecting the skimmers is fairly simple, Galloway said, without going into any details.

Making it easier is that the key to open the gas pump panels at Circle K is universal. In other words, the exact same key opens any gas pump panel — not just the ones at the Circle K, Galloway said.

Detectives now are attempting to determine when the skimmers were installed and by whom.

So far, police have not received any reports of credit card fraud that might be tied back to the skimmers, Galloway said, but detectives will be checking into that, too.

Galloway, who said he's been a victim of credit card skimming, stressed that people with credit or debit cards should regularly check their statements for purchases that they did not make.

There also are apps that send a push alert to cardholders' phones each time a purchase is made with a particular card, Galloway said, noting that customers should check with the company that issued the card to learn about the apps.